I like to take occasional tolerance breaks from coffee completely.
I also like to drink much less than the max before I start feeling bad, so that if I have a really long day I can drink more than usual and really feel the effects, without needing to have so much that I have a bad trip(Some of the Starbucks drinks will make me feel like crap with just one of them).
There seems to be studies saying coffee drinkers live longer, and it tastes great, so I do enjoy a daily cup or two of coffee or tea, but I would not want a lifestyle where I couldn't have no caffeine at all most days if I did want to.
I mention this one a lot, but removing a lot of personal side projects from my life has helped me tremendously. I think of it kind of like decluttering, but in the time domain.
I've even mostly changed my stance on open source from "Always use it" to "Avoid things that cause vendor lock in, otherwise prefer FOSS if convenient, but don't hesitate to use proprietary".
Of course you might not have easily discardable projects to free up time with, if you're busy with work or study grinding.